Fig 6 - uploaded by Gregor Borg
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Vero Liberator comminution system: (a) showing the casing cylinder that contains the vertical axle with three levels of hammer tools. note the small physical footprint of this 100 to 130 t/h throughput unit; (b) as installed and operating at a mine site in South africa. the core unit is the vertical cylinder in the middle.
Source publication
Mining and mineral processing industry are under pressure from political and social stakeholders to deliver products more sustainably with a much smaller environmental impact. Technical innovations to achieve these goals include reduction in energy consumption, waterless mineral processing, coarse particle liberation, and safe dry stacking of taili...
Contexts in source publication
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... Vero Liberator technique was invented in 2012 by PmS Gmbh, Germany (Figure 6a), and market entry was achieved in late 2016 [9]. as the first global player in the mining world, anglo american plc, ordered four bespoke Vero Liberator units so far, all specially designed to be used in long-term industrial-scale pilot tests at their operations. ...
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... integration of the Vero Liberator is part of the anglo american FutureSmart mining tm programme, which aims to increase the efficiency in each step of the mineral resource value chain. the technique has now achieved the technical readiness Level trL 7 with wo machines in operation for over two years in South africa (Figure 6b), a third unit awaiting shipment and the fourth machine currently being manufactured. anglo american and PmS are cooperating closely to bring the Vero Liberator technology to the next trL. ...
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... american and PmS are cooperating closely to bring the Vero Liberator technology to the next trL. the Vero Liberator (Figure 6a, b) currently operates in the 100 to 130 t/h class, but up-scaling and down-scaling is currently under way. maximum feed size for the current Vero Liberator model is approximately 120 mm in diameter. ...
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... on the input material from mining, this could be material from a primary crusher or could even replace the primary crusher itself plus subsequent crushing and milling stages. the comminution unit sensu stricto has a relatively small physical footprint of 2.5 × 2.5 m only ( Figure 6a) and has been built in a modular fashion and is easy to transport, assemble, modify or service according to customer's demands ( Figure 6b). the relatively small unit size also allows for semi-mobile use for in-pit crushing and conveying (iPcc) operations. ...
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... on the input material from mining, this could be material from a primary crusher or could even replace the primary crusher itself plus subsequent crushing and milling stages. the comminution unit sensu stricto has a relatively small physical footprint of 2.5 × 2.5 m only ( Figure 6a) and has been built in a modular fashion and is easy to transport, assemble, modify or service according to customer's demands ( Figure 6b). the relatively small unit size also allows for semi-mobile use for in-pit crushing and conveying (iPcc) operations. ...
Citations
... In contrast to these finely intergrown "problematic ores", there are also lithium ores that exhibit straightforward, polygonal mineral intergrowths, where optimal separation of valuable and host rock minerals can be achieved using suitable comminution and liberation techniques. A particularly illustrative example is that of pegmatitic spodumene ores from Pilgangoora Mine in North West Australia [31], where spodumene was optimally liberated using the Vero Liberator © comminution technique [10] ( Figure 17). After reaching the target particle size through comminution and classification using wet or dry screening methods or centrifugal forces in separation cyclone technology, lithium concentrate production techniques are employed. ...
This treatise describes the geogenic enrichment and anthropogenic value chains of lithium from the Earth's mantle to ore mineral concentrate. This includes, on one hand, the enrichment processes from the Earth's mantle through the oceanic and continental crust to highly fractionated granitic greisens, pegmatites, veins, and volcanic tuffs, on the other hand, the basic methods of exploration, mining, and processing of ores up to marketable lithium ore mineral concentrates.
Due to the very small radius of the lithium atom and ion, there are some remarkable peculiarities, such as the highly incompatible element behaviour of lithium in most magmatic processes. As a result, lithium becomes enriched from extremely low concentrations in the Earth's mantle through basaltic melts at mid-ocean ridges and andesitic melts over subduction zones to highly fractionated granitic melts of second order (S-type) granites, pegmatites, and mineralized quartz veins as well as rhyolitic tuffs, and finally as tuff-derived clays. Typical lithium deposits are found especially in hydrothermally altered granites, so-called greisens, coarse-crystalline to giant pegmatites, mineralized quartz veins, and fine- to very fine-crystalline volcanic tuffs and clays. The most important lithium minerals are spodumene (6-9 % Li2O), petalite (about 4.8 % Li2O), lepidolite (about 4.2 % Li2O), and zinnwaldite (2-5 % Li2O), all of which are silicate or hydrosilicate minerals with different crystal structures (Bowell et al. 2020). Whereas spodumene belongs mineralogically to the clinopyroxene group, the other three mentioned Li minerals are micas, i.e. sheet silicates, and petalite is a framework silicate.
The exploration of lithium deposits initially utilizes geological surface mapping and geochemical rock and soil analysis to identify lithium-bearing pegmatites, greisens, and tuffs. Ore bodies that are visibly exposed at or identified near the earth’s surface can be explored down to depths of several hundred meters relatively accurately with deeply penetrating geophysical exploration methods. Ultimately, percussion and core drilling with increasingly tight spacing of drilling grids and subsequent geochemical analysis of the drill samples provide the necessary predictive accuracy for technical and economic feasibility studies. It is important to note that tabular, sub-vertical pegmatitic Li ore bodies and mineralized vertical to sub-horizontal quartz veins differ fundamentally both in exploration and mining from large-volume Li-greisens and tabular, sub-horizontal Li-tuffs or Li-clays. The costs of the individual exploration and development stages of a deposit up to the operating mine usually increase exponentially, while the geological risk decreases with the increasing degree of information. The final investment decision for the establishment of a mine is ultimately made based on a bankable feasibility study. The type of mining, i.e. the extraction of the ores, can be minimally invasive either in open-pit or underground mining, depending on the geometry of the ore body and optimal environmental compatibility.
Lithium minerals usually do not represent the only valuable components of the ores. In pegmatites, mineralized quartz veins, and greisens, there is often an association with cassiterite (SnO2), wolframite (WO4), chalcopyrite (CuFeS2), sphalerite (ZnS), rare earth minerals such as monazite (Ce,La,Nd,Sm)(PO4), or the mixed mineral group columbite-tantalite. The ore mineral size and shape, as well as the highly different physical and chemical properties of these valuable minerals, make the extraction of these valuable minerals very laborious, as separate processing steps are usually necessary to extract the individual ore mineral concentrates, each of which incurs significant capital (CapEx) and operating costs (OpEx). With generally very low total Li contents of usually less than 2 %, this poses a significant challenge, especially since the residual materials should also be subjected to reuse or for disposal. However, there is still considerable potential for innovation in many processing steps of mineral raw materials - and here especially of primary mineral lithium raw materials - which, for example, enable significant reductions in energy costs, in minimising the CO2 footprint and are thus ultimately of both ecological and economic necessity.
... The heat mainly comes from two sources: the inner source is the release of the elastic energy accumulated in the particle at the moment of breaking apart, the outer one is the friction within the particles and/or within particles and grinding medium (these partly might contribute to the grinding process) and/or within the grinding medium only (that purely is waste if the process does not result better quality at higher temperatures). An overall 1% of energy input causes breakage (Borg et al. 2020). ...
... It cannot be found literature to test equally high force or tension resulted by the transfer of the kinetic energy that can provide the mass of the particle itself. Instead, it seems like the energy accumulation without relaxation time generates resonances that differs regarding the material composition and/or physical properties, suffering reflections and deformation on the particle contact surfaces resulting great tensions than final disintegration (Borg et al., 2020). Even further, how it can be continuously increased to maintain the comminution ratio high when a particle loses mass during the process. ...
... The product can be graded by grain size and the liberation factor can reach to almost 100%. (Borg et al., 2020) ...
The mining industry has traditionally relied on conventional fossil-based fuel sources to meet its growing energy demand. The industry is now tasked with responding to the challenges of increasing fuel prices while commodity prices tighten, resulting in ever-narrowing operating margins and increased opposition from communities to new conventional energy sources. So far, research about such decision-making on the use of renewable energy in production scheduling (PS) problem for open pit mining operations is underdeveloped. Due to the conflicting nature of economic and environmental objectives, the PS becomes a multi-objective problem. In this paper, a multi-objective gravitational search algorithm is used to provide Pareto optimal solutions which present the possible tradeoff between the cost and environmental objectives of the PS problem. To solve the problem, the weighted sum method is applied to convert multi-objective optimization to scalar optimization. The numerical results demonstrate the
effectiveness of the proposed approach in solving multi-objective PS problems.
Gregor Borg (2023) Grundlagen der Metallogenese, Exploration und Gewinnung mineralischer Lithiumlagerstätten. in: SPLEEN - Volume 02 - (Eds. U. Blum & R. B. Wehrspohn) Series on the Potentials of Lithium in the Economy, Environment and Nature
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Diese Abhandlung beschreibt die geogenen Anreicherungs- und anthropogenen Wertschöpfungsketten des Lithiums vom Erdmantel bis zum Erzmineralkonzentrat. Dies umfasst einerseits die Anreicherungsprozesse vom Erdmantel über die ozeanische und kontinentale Kruste bis in hoch fraktionierte granitische Greisen, Pegmatite und Adern sowie vulkanische Tuffe; andererseits werden die grundlegenden Methoden der Aufsuchung, des Abbaus und der Prozessierung der Erze bis hin zu Lithiumerzkonzentraten erläutert.
Aufgrund des sehr kleinen Radius des Lithiumatoms und -ions ergeben sich einige bemerkenswerte Besonderheiten, wie zum Beispiel das höchst inkompatible Elementverhalten des Lithiums bei den meisten magmatischen Prozessen. Hierdurch reichert sich das Lithium von äußerst geringen Konzentrationen im Erdmantel über basaltische Schmelzen an mittelozeanischen Rücken sowie andesitische Schmelzen über Subduktionszonen bis in höchst fraktionierte granitische Schmelzen zweiter Ordnung von (S-Typ) Graniten, Pegmatiten und mineralisierten Quarzadern sowie rhyolitischen Tuffen und schließlich Tonen an. Besonders in hydrothermal alterierten Graniten, sogenannten Greisen, grobkristallinen bis riesenwüchsigen Pegmatiten und mineralisierten Quarz-adern sowie fein- bis feinstkristallinen Tuffen und Tonen finden sich die typischen Lithiumlagerstätten. Die wichtigsten Lithiumminerale sind Spodumen (6-9 % Li2O), Petalit (ca. 4,8 % Li2O), Lepidolith (ca. 4,2 % Li2O) und Zinnwaldit (2-5 % Li2O), allesamt Silikat- bzw. Hydrosilikatminerale mit unterschiedlicher Kristallstruktur (Bowell et al. 2020). Während der Spodumen zu den Klinopyroxenen gehört, sind die drei übrigen genannten Li-Minerale Glimmer, d. h. Schichtsilikate, und der Petalit ein Gerüstsilikat.
Die Exploration von Lithiumvorkommen nutzt zunächst geologische Oberflächenkartierungen und geochemische Gesteins- und Bodenanalytik zur Identifikation von lithiumführenden Pegmatiten, Greisen und Tuffen. Mittels geophysikalischer Tiefenerkundung lassen sich die sichtbar anstehenden oder oberflächennah identifizierten Erzkörper bis in Tiefen von mehreren hundert Metern räumlich relativ genau erkunden. Letztlich müssen Meißel- und Kernbohrungen mit zunehmend engem Bohrraster und anschließender geochemischer Analytik der Bohrproben die notwendige Prognosesicherheit für technische wie wirtschaftliche Machbarkeitsstudien liefern. Dabei unterscheiden sich eher tabular-subvertikale pegmatitische Li-Erzkörper und mineralisierte vertikale bis subhorizontale Quarzadern von großvolumigen Li-Greisen und tabular-subhorizontalen Li-Tuffen oder Li-Tonen grundlegend. Die Kosten der einzelnen Explorations- und Erschließungsstadien einer Lagerstätte bis hin zum operierenden Bergwerk steigen dabei meist exponentiell, während das geologische Risiko mit zunehmendem Informationsgrad abnimmt. Die abschließende Investitionsentscheidung für die Einrichtung eines Bergwerks erfolgt schließlich auf Basis einer bankfähigen Machbarkeitsstudie. Die Art der bergbaulichen Gewinnung, d. h. der Abbau der Erze, kann, je nach Geometrie des Erzkörpers und optimaler Umweltverträglichkeit, minimalinvasiv entweder im Tagebau oder untertägig erfolgen.
Zumeist stellen die Lithiumminerale nicht die einzigen Wertstoffträger der Erze dar. In Pegmatiten, mineralisierten Quarzadern und Greisen liegt häufig eine Vergesellschaftung mit Kassiterit (SnO2), Wolframit (WO4), Chalkopyrit (CuFeS2), Sphalerit (ZnS), Seltene-Erden-Mineralen wie Monazit (Ce, La, Nd, Sm)(PO4) oder der Mischkristallmineralgruppe Columbit-Tantalit vor. Die Erzmineralgröße und -gestalt sowie die physikalisch wie chemisch höchst unterschiedlichen Mineraleigenschaften dieser Wertminerale machen die Gewinnung (Ausbringung) dieser Wertminerale sehr aufwendig, da zumeist separate Aufbereitungsschritte zur Gewinnung der einzelnen Erzmineralkonzentrate nötig sind, die jeweils signifikante Investitions- (CapEx) und Betriebskosten (OpEx) verursachen. Bei üblicherweise sehr geringen Gesamterzgehalten von meist unter 2 % stellt dies eine erhebliche Herausforderung dar, zumal auch die Restmaterialien einer Nachnutzung oder Deponierung zugeführt werden müssen. Allerdings gibt es in vielen Aufbereitungsschritten mineralischer Rohstoffe – und hier insbesondere auch primärer mineralischer Lithiumrohstoffe – noch beträchtliche Innovationspotenziale, die z. B. deutliche Reduzierungen der Energiekosten und des CO2-Fußabdrucks ermöglichen und somit letztlich sowohl von ökologischem wie ökonomischem Interesse sind.